: 177 

J6 No. 746 

921 U. S. DEPARTMENT OF AGRICULTURE, 

opyl WEATHERBUREAU. 

CHARLES F. MARVIN. Chief. 



mSTRUOTIONS FOR THE 

INSTALLATION AND MAINTENANCE OF 

MARVIN WATER-STAGE REGISTERS 

WITH SPECIFICATIONS. 



CIRCULAR J, INSTRUMENT DIVISION. 



Bt 



ROY N. COVERT, 

Meteorologist. 




WASHINGTON: 

GOVERNMBNT PRINTING OFPICS. 

1921. 




PIPING FOR Float and counterweight attached to PiER OF SUSPEN- 
SION BRIDGE. CINCINNATI, OHIO. PLATFORM AT TOP OF PIPE HAS 

APPROACH THROUGH FLOOR O^ BRIDGE. 



W. B. No. 746 

U. S. DEPARTMENT OF AGRICULTURE, 
U. i WEATHER BUREAU. 

CHARLES F. MARVIN, Chief. 



INSTRUCTIONS FOR THE 

INSTALLATION AND MAINTENANCE OF 

MARVIN WATER-STAGE REGISTERS 

WITH SPECIFICATIONS. 



CIRCULAK J, INSTRUMENT DIVISION. 



Bt 



EOY N. COVERT, 

Meteorologist. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

1921. 



re 



11 2^' 



LIST OF ILLUSTRATIONS. 



Piping for flout and countenveiglit attached to pier of Suspension 

Bridge, Cincinnati, Ohio Frontispiece 

Pago. 

Fig. 1. Installation of float and counterweight pipes within bridge pier_ 7 

2. Float and counterweight pipes attached to outside of bridge pier_ 8 

3. Photograph of transmitter together with top flange for attach- 

ment to float pipe 10 

4. Float and counterweight 10 

5. Indicator; exterior view 11 

6. Indicator; interior view, cover removed 11 

7. Wiring diagram for direct connection 16 

8. Wiring diagram using relays for local circuit 18 

9. Wiring diagram using lightning arresters 19 

10. Wiring diagram for recorder or teleregister 22 

11. Teleregister for use in place of indicator 23 

(2) 



I 



LIBRARY OF CONGRESS 



tlVEo 



0CT«8192/ 



;J2-52?7 



rs4 



3 

I 



TABLE OF CONTENTS. 



Page. 

I. General description .5 

II. Float pipe -- 5 

III. Installation of float pipe within pier 6 

IV. Float pipe attached to outside of pier (3 

V. Transmitter 9 

VI. Indicator 9 

VII. Installation of register 10 

VIII. Specifications for installation of float and counterweight pipes 

within bridge pier 10 

IX. List of material required 11 

X. Specifications for installation of float and countenveight pipes 
together v/ith platform and ladder approach ; for use with water- 
stage register at Charleston, W. Va 11 

XI. Installation of transmitter 14 

XII. Installation of indicator or recorder 14 

XIII. Wiring 14 

XIV. Protection against lightning 19 

XV. Care of register 20 

XVI. Water-stage recorder 22 

(3) 



INTRODUCTION. 



The work of the Weather Bureau as regards the observation of 
river stages has been steadily increasing, keeping pace with the 
growth of industry, agriculture, and commerce. In addition to the 
large number of river gages which require direct reading, a consid- 
erable number of the Weather Bureau stations along the important 
rivers are equipped with recording or indicating registers. Besides 
the advantage of maintaining a continuous record of the river stages 
for stream-flow and flood-forecasting studies, these instruments are 
of particular value at the larger stations, since the height of the 
water can be furnished at a moment's notice in answer to inquiries, 
often urgent, received by telephone or otherwise. 

Up to the present time the installation of these gages has been 
handled almost entirely by correspondence; hence the need of a 
publication w^hich embodies the experience of the bureau, furnishes 
information not readily available heretofore, and therefore renders 
the installation of recording gages more simple. 

(4) 



i 



liNSTRUCTIONS FOR THE INSTALLATION AND MAINTENANCE 
OF MARVIN WATER-STAGE REGISTERS, WITH SPECIFICA- 
TIONS. 



I. GENERAL DESCRIPTION. 

1. Types of registers. — There are two principal types of registers 
in use in the Weather Bureau, namely, the Marvin and the Friez. 
The Marvin gage is employed much more generally than the others 
and the following information deals with that gage. However, the 
installation of float and counterweight pipes would be practically the 
same for any of the registers used. Information regarding registers 
other than the Marvin will be furnished on request. 

2. Arrangement of parts. — The Marvin register is composed of two 
principal parts : One, the float mechanism or transmitter, located at 
the river; the other, the indicator, or occasionally a recorder, in- 
stalled in the distant office and connected electrically with the trans- 
mitter. Stages of the river are read from the indicator to feet and 
tenths of a foot. Besides the instruments proper the register re- 
quires for its operation a float pipe that is essentially a still well, to 
which the river water has access at the bottom through lateral inlet 
pipes. A copper float rests on the surface of the water in the pipe, 
the float being suspended by a perforated bronze tape passing over a 
sprocket wheel in the transmitter. The weight of the float and tape 
is counterbalanced by a weight free to move in a smaller pipe parallel 
to the float pipe ; all as shown in the illustrations. Vertical motion 
of the water in the pipe is thus communicated to the transmitter, 
which in turn completes the electrical circuit to the indicator for each 
rise or fall of a tenth of a foot. 

3. The Friez gage differs from the Marvin in being non-electrical 
with the recorder placed directly over the float pipe. 

II. FLOAT PIPE. 

4. Location. — The float pipe may be attached to the outside of a 
bridge pier, as illustrated in the frontispiece, or better still installed 
within the pier while the bridge is in course of construction, as 
shown in figure 1. 

5. The pipe should be located where oscillations of the water in 
the float pipe due to wave action or excessive current are least. It 
is stated by the official in charge at St. Louis that to go too far toward 

(5) 



the center of the stream results in placing the gage where oscillations 
are very likely because of whirls in the swifter current, while an 
installation too near shore results in excessive oscillations due to wave 
action. Each installation should therefore be made so as to mini 
mize these effects. 

III. INSTALLATION OF FLOAT PIPE WITHIN PIER. 

6. A tyjncol installation of a float pipe within a bridge pier is 
illustrated in figure 1. The vertical portion, A, is 8-inch standard 
wrought-iron pipe with flanged and bolted couplings. An 8-inch T, 
B, is placed at its lower end to which the horizontal 8-inch pipes, C 
and D, are attached. These latter make up the inlet for the water 
and are placed so as to make an angle of 60° with the direction of the 
stream flow. The inlet pipe should if practicable be located a little 
below the lowest water stage experienced. In order that waves in 
the river may not cause fluctuations in the height of the water in the 
float pipe, nozzles E and F are screwed to the ends of the inlet pipe 
and the wave action is thereby damped. The openings in the noz- 
zles- shown are three-fourths of an inch in diameter, but should be 
more if the river deposits silt rapidly. 

7. Upper ends of float and counterweight pipes. — The float pipe 
extends to a height of about 30 inches above the top of the pier. 
This upper end is not threaded, but made smooth and level, and 
surmounted by the top flange, G, which is attached to the pipe by 
means of three set screws. The base plate, H, is screwed to the top 
flange, and constitutes the support for the transmitting mechanism. 
The IJ-inch counterweight pipe is shown at I. To complete the 
installation of a register, the transmitter and indicator are con- 
nected electrically to each other and to a battery, as further described 
below. 

IV. FLOAT PIPE ATTACHED TO OUTSIDE OF PIER. 

8. The method whereby the float pipe may be attached to the out- 
side of a bridge pier is illustrated in figure 2. It will be noticed 
that no horizontal inlet pipe is required, but that otherwise the same 
sized float and counterweight pipes are used, and their lengths and 
arrangement are similar to those shown in figure 1. The principal 
difficulties inherent in such an installation are found in the construc- 
tion and attachment of brackets for supporting the pipe, since the 
brackets are of differing dimensions to conform to the shape of the 
pier. Also, the pipe being external to the pier, there is possibility of 
injury due to passing objects in the stream, and the distance of the 
upper end of the pipe from the top of the pier requires the construc- 
tion of a platform and means of approach thereto. The illustration 



I B 



z 



R£CF-SS-iN PILR 
FOR TRANSMITTE-R 



PL AM 



77 






3fKSt-. PLATE. 




FASTE^NER 'i- SEPARATOR 
roR. Fl_Oi\T^CTwr PIPE,S 



B-IIM GAUV. WROUGHT-- 
IRON FUOAT PIPE, WITH 
C I. STANDARD FLANGES 

i_j-IN. MALLEABLE -IRON 
CAP 



8-iN, GALV WROUGHT 
IRON PIPE. SET AT 
ANGLE. OF 4)0° WITH 
STREAM. 



CAST-IRON NOZZLE 
•(5E.e, J5RWC. los; \ 



FiQ. 1.— Installation of float and countei-weight pipe within bridge pier. 



8 




ZERO &AGC. ->. 



Fig. 2. — Float and counterweight pipes attached outside of bridge pier. 



9 

shown is taken from plans of an installation of a Marvin register 
at Charleston, W. Va., and specifications for the work at this station 
are given below. 

Following is a detailed description of the instrumental parts of 
the equipment : 

V. TRANSMITTER. 

9. The troMsmitter consists essentially of a contact-making device 
which responds to changes in the level of the water in the float pipe. 
Eeferring to figure 3, A is a two-way mercury switch which selects 
the wires for the current flow in a three-wire circuit, while B is a 
second switch actuated by the governed clock mechanism, C, which 
serves to determine the duration of the contact and as a result the 
positiveness of the action of the electromagnets of the indicator. A 
perforated bronze tape, D, is passed over the sprocket wheel, E, and 
thence to the wheel F. The end of the tape below wheel F carries 
a counterweight, while at the other end of the tape is a 6-inch copper 
float which rests on the surface of the water in the float pipe. The 
float and counterweight are shown separately in figure 4. Changes 
in the height of the water cause the sprocket wheel, E, to rotate, 
which rotation in turn tilts the mercury switch. A, and releases the 
clockwork C. The electric circuit is thus closed by switch, B, for 
each tenth of a foot change of water level and the rising or falling 
magnet of the indicator energized, which produces in turn the motion 
of the indicator hand over the dial. (See fig. 5.) A removable 
iron plate, H, closes the top of the float pipe. This plate keeps 
much moisture from reaching the transmitter, and also prevents 
small articles from being dropped into the pipe. 

10. Transmitter dials^ reading of. — At G, figure 3, there is a pair 
of dials similar to those used in the anemometer, which, when prop- 
erly set, show the exact stage of the river. These dials are read in 
substantially the same manner as anemometer dials as described in 
Circular D, Instrument Division. 

11. Exposure to weather. — When the transmitter is exposed to the 
weather, it is protected by two copper covers, an inside one that 
covers the instrument proper and a larger outside cover hinged to 
the base plate and locked to the plate with a padlock. When placed 
in a recess in a pier, the outer copper cover is omitted. 

VI. INDICATOR. 

12. Description. — This portion of the register is illustrated in 
figures 5 and 6. It consists essentially of two electromagnets, one 
for rising and one for falling stages of the river, A and B, respec- 
tively, which produce the desired rotation of the hand over the dial 
through the intermediate gear wheels. The electrical connections are 

57710—21 2 



10 

made to the binding posts, C, which are also shown on figure 7, 
diagram of circuits. The arrow point of the face of the dial shows 
at any time whether the river is rising or falling. When the point 
is down the river is falling and vice versa. 

\t:i. installation of register. 

13. Site for register. — The first steps to be taken preliminary to 
installing a recorder are to secure the necessary site for the float and 
inlet pipes and to make certain that dependable wire seiTice is 
available. Usually a bridge pier is chosen where there is a consider- 
able depth of water present when the lowest stages of the river are 
reached. Another factor entering into the problem of site is the 
distance of the transmitter from the roadway of the bridge. These 
matters are handled in detail by the official in charge of the river sta- 
tion, under the direction of the central office, where special drawings 
and specifications are customarib/ prepared. Sometimes it is also 
necessary to design a suitable approach from the bridge roadway or 
walk to the top of the pier and the transmitter. 

14. Securing frofosols for work. — The work is usually done on 
contract, proposal forms being submitted to three or more bidders 
in the customary manner. 

To illustrate what material and labor are required, the following 
brief specifications are submitted which apply to figure 1 : 

VIII. specifications for installation of float and cotjnter^veight 
PIPES \^t:thin bridge pier. 

15. Assembly of pipe. — The float pipe shall be made up of sections 
of 8-inch standard weight galvanized wrought-iron pipe, with a total 
overall length of nearly 33 feet; the joints formed of standard cast- 
iron bolted flanges. The contractor should carefully verify for him- 
self the dimensions shown on the drawing. 

16. Verticality. — Attention is invited to the necessity of securing 
absolute verticality of the pipe in its final position. When the float 
pipe is in position the top end will be covered temporarily to prevent 
any refuse from dropping in. 

17. Nozzles. — The ends of the inlet pipes are closed by special cast- 
iron nozzles screwed to the pipe, as indicated in figure 1. These cast- 
ings will be furnished by the Weather Bureau, but the piping and 
such fittings and material as are required for the installation will 
be provided by the contractor. The top end of the float pipe shall 
be cut off square and true and not screw-threaded, the flange being 
attached by set screws. 

18. 2' he counterweight pipe shall have an overall length of nearly 
26 feet 4 inches, and be made up of sections of IJ-inch standard 




ENT TO FLOAT PIPE. 




FLOAT AND COUNTERWEIGHT. 




INDICATOR, EXTERIOR VIEW. 




INDICATOR, INTERIOR VIEW, COVER REMOVED. 



11 

weight, galvanized wrought-iron pipe closed at the bottom with a 
malleable-iron cap made water tight. Screw couplings shall be used 
at joints, all the joints to be water tight. The center of the pipe 
will be accurately spaced 6J inches from the center of the float pipe, 
and it will be necessary to slightly cut away the flanges of the float 
pipe to permit of this spacing. The ends of the sections of this pipe 
shall be cut off square and true and left perfectly smooth on the 
inside, without any burr or other projections that would in any way 
interfere with the free movement up and down through the pipe of 
the counterweight. The top end of the counterweight pipe shall be 
installed so as to stand exactly If inches higher than the top of the 
float pipe, and be cut off true and square without a thread. The rela- 
tion of float and counterweight pipes is shown in drawing. 

19. Protection from corrosion, — All iron parts will be carefully 
galvanized to prevent corrosion, and where such galvanizing is re- 
moved during assembly by thread cutting, drilling, etc., these parts 
and such others as are scarred during assembly will be painted with 
red lead. 

IX. LIST OF MATERIAL REQUIRED. 

Two pieces 8-inch galvanized standard wrought-iron pipe each 7 
feet long threaded at both ends. 

One standard 8-inch cast-iron flanged T. 

Two pieces 8-inch galvanized standard wrought-iron pipe each 16 
feet 6 inches long threaded at both ends except one piece cut off 
square and true without threads. 

Three standard 8-inch cast-iron flanges. 

Two pieces IJ-inch galvanized standard wrought-iron pipe with 
couplings to give over-all length of 26 feet IJ inches, one end to be 
cut off square and true without threads. 

One IJ-inch malleable-iron cap. 

Five cast-iron separators for spacing float and counterweight 
pipes. 

Two 8-inch cast-iron nozzles (furnished by Weather Bureau). 

X. SrECIFICATIONS FOR THE INSTALLATION OF FLOAT AND COUNTERWEIGHT 
PIPES, TOGETHER WTTH PLATFORM AND LADDER APPROACH; FOR USE 
WITH WATER-STAGE REGISTER AT CPIARLESTON, W. VA. 

20 (1). General specifications. The work will consist principally 
of the following parts, all labor and material with certain exceptions 
to be provided by the contractor : 

(a) The installation of wrought-iron float and counterweight 
pipes on special brackets; all substantially as shown on Weather 
Bureau drawing Ko. 163 (see Figure 2), the same to be placed on 



12 

the downstream side of the pier bearing the United States gauge, on 
the Charleston and South Side highway bridge. 

(b) The construction and installation of a platform about 8 feet 
square, placed near the top of the pier and provided with iron ladder 
to give access to the float mechanism, which will be mounted later 
at the top of the float pipe. 

21. The work is to be done, if practicable, essentially as shown in 
detail on drawing No. 163, and any deviation therefrom will be made 
only after consultation with the engineer in charge of the work. 

22. (2) The float pipe will be made up of sections of 8-inch stand- 
ard-weight, galvanized wrought-iron pipe, with a total over-all length 
of nearly 74 feet, the joints formed of standard cast-iron bolted 
flanges. This pipe will be held in as exactly a vertical position as 
possible by means of several heavy wrought-iron brackets placed as 
shown in blue print, the flanged joints of the pipe resting on top of the 
outer ends of the brackets, so that no slipping of the pipe is possible. 
The contractor will carefully verify for himself, from measurements 
made on the bridge pier, the dimensions of the brackets as shown on 
the drawing, inasmuch as the pier is " rock face," and the projections 
on the face of the pier may require some modification of the dimen- 
sions given. 

23. Verticality of pipe. — Attention is invited to the necessity of 
securing absolute verticality of the pipe in its final position. It is 
suggested that the float pipe be built up around a plumb line hung 
from a point at the top representing the final position of the center 
line of the pipe ; and then make sure that the brackets, when finally 
fastened to the side of the pipe, hold the several sections of the pipe 
accurately centered. To avoid the disturbing influence of the wind, 
etc., a fine wire can be used for the line, and a weight, say, of 15 or 
20 pounds for the plumb bob. This plummet should be lowered in- 
side the section of pipe so as to be sheltered from wind disturbance, 
etc. When the float pipe is in position the top end will be covered 
temporarily to prevent any refuse from dropping in. 

24. Nozzle. — The bottom end of the float pipe is closed by a special 
cast-iron nozzle screwed to the pipe, as indicated in the blue print. 
This casting is furnished by the Weather Bureau, and likewise the 
cast-iron top flange to which is attached the base for supporting the 
float or transmitter mechanism. The top end of the float pipe must 
be cut off square and true and not screw threaded, the flange being 
attached by set screws. The contractor is required to attach the 
flange only, the attaching of the transmitter base being left until 
later. 

25. (3) The counterweight pipe has an overall length of nearly 
43 feet, and is made up of sections of IJ-inch standard weight, gal- 
vanized wrought-iron pipe closed at the bottom with a malleable- 



13 

iron cap made water tight. Screw couplings will be used at the 
joints, all water tight. The center of the pipe will be accurately 
spaced CJ inches from the center of the float pipe, and it will be 
necessary to slightly cut away the flanges of the float pipe to permit 
of this spacing. The ends of the sections of this pipe must be cut 
off square and true and left perfectly smooth on the inside, without 
any burr or other projections that would in any way interfere with 
the free movement up and down through the pipe of the counter- 
weight. The top end of the counterweight pipe must be installed 
so as to stand exactly If inches higher than the top of the float pipe, 
and be cut off true and square and without a thread. The relation 
of float and counterweight pipes is shown in blue print in detail of 
bracket, and in assembly of top flange and support for float mecha- 
nism. 

26. (4) The platform to be provided will be carried on two 8-inch 
standard weight, galvanized, wrought-iron channels, securely bolted 
to the sides of pier immediately below the cap and suitably braced 
by means of steel angles, all as shown in drawing. A substantial 
floor of If by 6 inch cypress planks will be laid on three 4 by 4 inch 
cypress sleepers bolted to the channels; all thoroughly painted. 
The floor planks wil be spaced about one-fourth inch apart. 

27. A suitahle galvanized-iron hand railing Z\ feet high, made of 
If-inch standard wrought-iron pipe, will be placed around the ex- 
posed edges of the platform. 

28. The iron ladder^ shown in detail No. 10 in blue print, will be 
made up practically as illustrated, and one of the planks of the 
bridge walk will be replaced by another somewhat longer to pro- 
vide suitable bracing for the ladder. If necessary it will also be at- 
tached to the railing of the bridge. Should the top of the railing and 
the ladder be rather difficult of access from the bridge walkway, 
some simple form of steps will be attached to the railing on the side 
to remedy the trouble. 

29. (5) No cofferdam will be needed to install the pipe while the 
river is low. 

30. (6) All iron parts will be carefully galvanized to prevent 
corrosion, and where such galvanizing is removed during assembly 
by thread cutting, drilling, etc., these parts and such others as are 
scarred during assembly will be painted with red lead. 

31. Material to Complete Installation. — When the piping has been 
placed in position the following equipment will be needed to com- 
plete the installation : 

One water-stage register, two parts : 

(1) Transmitter. 

(2) Indicator or recorder. 
One copper float. 



14 

One phosphor bronze tape, perforated. 
One counterweight. 
One cast-iron base plate for float pipe. 
One cast-iron top flange for float pipe. 

One small bottle of mercury for the mercury switch B of trans- 
mitter. 

XI. INSTALLATION OF TRANSMITTER. 

32. Details of work. — Referring to figure 3, the cast-iron top flange 
with the attached base plate is first placed over the top of the float 
pipe and secured with set screws. The transmitter should then be 
set up on blocks about 6 inches high so that easy access may be had 
to the float pipe and the cover to the same readily inserted. Then 
the float will be hooked to the perforated end of the phosphor-bronze 
tape and lowered to the surface of the water in the pipe. Next the 
other end of the tape will be threaded through the cover and the 
hole in the base of the instrument, and the counterweight attached 
and lowered into its pipe. Care should be taken not to kink the tape. 
The blocking may then be removed from under the transmitter and 
the latter attached to the base plate with the three screws at the cor- 
ners. Lastl}' the ivory cups of switch, B, will be nearly filled with 
mercury, using a medicine dropper. Too much mercury should not 
be used nor any particles allowed to fall on the brass portions of the 
instrument. 

XII. IXSTALI^TION OF INDICATOR OR RECORDER. 

33. The indicator mere!}" needs to he securely fastened to the wall 
in the office where it may be read conveniently and the electrical con- 
nections readily made thereto. In order to provide easy access to the 
mechanism of the indicator the cover of the instrument is hinged to 
the case mounted on the wall, and, should it be necessary, the whole 
mechanism can be entireh^ removed from the wall by simply with- 
drawing the long brass pin forming the hinge. A recorder should be 
placed on the instrument stand. 

XIII. WIPaNG. 

34. The loire and battery service is customarily secured from the 
local telephone company at a certain rate per annum. It is possible, 
however, to maintain battery in the Weather Bureau office, but the 
storage-battery service furnished by a telephone company is gener- 
ally more satisfactory, and unless constant care of a battery can be 
given by the station force, rented battery service is more dependable. 

35. Type of hattery. — Occasionally dry cells are employed; Water- 
bury primary cells would do better, but a well cared for storage bat- 
tery is preferable. Three wires, preferably not smaller than No. 18 



15 

gage, are required for a metallic circuit and a battery the voltage of 
which is dependent upon the length of circuit. Details relative to the 
electrical connections are given below. 

36. Methods of loiring. — Figure 7 illustrates three methods of 
wiring, preference being given to the '3-wire metallic circuit A. The 
first alternative, B, is quite similar, excepting for the use of a 
grounded circuit from the battery to the transmitter. The second 
alternative, C, is least desirable and necessitates a change in the 
connection and insulation of the binding posts of the transmitter. 
It will be noticed that the line wires are attached to the two upper 
binding posts of the indicator, the lower instead of the middle post 
being grounded. 

37. Grounds. — The middle binding post of the transmitter is 
attached direct to the base and will probably be well grounded 
through the float pipe, but if this is not sufficient a wire should be 
run from the post to the metal work of the bridge, a car track, or 
a,ny well-grounded piping that may be reached. Grounds ma^^ be 
made to the indicator or battery by connection to the water piping 
within the building where they are located, or to specially constructed 
grounds outside. For the latter, a ^V-inch copper plate of about 10 
square feet may be used, buried in permanently moist earth, with a 
good-sized copper wire or a cable reaching to the surface and thence 
to the instrument. A piece of 1-inch galvanized-iron pipe driven 
into the earth also makes a good ground. However, water-pipe 
grounds will usually be available and the ground wire may be readily 
attached by wrapping it about the pipe and soldering when the pipe 
has been drained, or preferably a suitable clamp for the pipe may 
be provided to which the ground wire would be soldered or screw- 
connected. 

38. PermaneQicy of wiring. — The wiring at the bridge and in the 
office should be carefully done and protected from injury by being- 
placed in conduit or other ducts. N^ecessary outside wiring at the 
bridge must be weatherproof. No. 16 rubber-covered wire in sherard- 
ized conduit would be most suitable for the connection from the 
transmitter to the telephone company's lines, which are usually run 
underground. 

39. Adjustment and operation of register. — The register will oper- 
ate with a battery current of from 0.2 to 0.3 of an ampere, and the 
circuit is closed only at relatively infrequent intervals. The proper 
battery voltage required to give positive action should be ascertained 
by trial. One way is to disconnect the three wires at the transmitter 
end of the circuit and join them together by means of a double con- 
nector or otherwise. Then energize each indicator magnet in turn by 
touching the proper line wire to its respective binding post. There 
should be a perfectly definite action of the mechanism both as regards 



16 




17 

the motion of the index hand and the throw of the arrow from rising 
to falling or vice versa. The battery voltage beginning at some rela- 
tively low value should be gradually increased while the test is in 
progress until its proper magnitude is determined. 

40. Strength of current. — Excessive current strength should be 
avoided, as it causes undesirable sparking at the mercury contacts. 
If the current is too small, the mechanism may fail to shift the indi- 
cator arrow, but might possibly move the hand after the arrow has 
been shifted. 

41. The successful action of the register depends fundamentally 
upon an adequate and stead}^ strength of current. The battery serv- 
ice must not be subject to interruption nor the voltage allowed to 
fluctuate greatly. However, the storage-battery service customarily 
furnished by a telephone company will usually be thoroughly de- 
pendable. ' 

42. Use of relays, — Occasionally a long circuit of wires as small as 
21 gauge becomes necessary, in which case relays have been success- 
full}^ applied as indicated in figure 8. Both batteries should be 
adjusted to give positive action of the electromagnets, using neither 
too much nor too little current. 

43. Two other adjustments are necessary before the register is 
ready for operation : First, the dial wheels of the transmitter should 
be set to read correct stages. This may be easily done by lifting the 
tape free of the sprocket wheel and revolving the latter until the 
dial reading corresponds to the true stage of the river according to 
the standard city gauge, when the tape is in position and the float 
and counterweight in equilibrium. The dials read to feet and hun- 
dredths, but it is only necessary to set them to read to the nearest 
tenth of a foot, since only changes of a tenth of a foot are trans- 
mitted and indicated. 

44. When the dials are revolved to produce any desired reading, 
the precaution should be taken to lift the rocking lever from contact, 
so that the rapid oscillations of this lever while the clock is in motion 
shall not cause possible injury to some of the clock mechanism. The 
final setting of the dials to the actual reading may also be accom- 
plished by loosening the set screw holding the sprocket wheel to its 
shaft, and then adjusting the dials to the desired value. As will be 
noticed, the position of the guide roller can be adjusted so that the 
counterweight tape centers accurately in its pipe. 

45. Setting Indicator. — Having ascertained the stage of the water 
at the river and made a final setting of the float and sprocket wheel 
so that the dial reading corresponds with that of the existing stage 
of the river, it will then be necessary to set the indicator hand so 
that its reading also indicates the true stage. This can be done by 



18 




19 

opening the indicator and simply revolving the large, main-notched 
wheel at the center of the back of the dial until the desired indica- 
tion of the index hand is produced. The arrow-head may also be set 
to indicate whether the river is rising or falling if this is known at 
the time, but it does not matter greatly whether the arrow is set or 
not as it will assume the right position when the first change of one- 
tenth of a foot in the stage of the river occurs. After this time the 
indicator readings and the stage of the river should correspond with 
each other at all times, unless there is some failure due to lack of 
battery of other faults in the system. 



TO TRANS M ITTE-R. 



-n 







{N>JlCr\TOK, 




TE.LE.~K.E.S.IST£.R. 



Fig. 9. — Wiring diagram using lightning arresters. 



XIV. PROTECTION AGAINST LIGHTNING. 

46. Use of lightning aiTesters. — The wiring for water-stage regis- 
ters is usually underground, but occasionally a pole line becomes 
necessary. It is a good rule followed by some telephone companies 
to use arresters, when the pole line exceeds four spans, and the same 
rule should be applicable to pole lines in connection with water- 
stage registers to protect the delicate and expensive raech^inism 
against lightning. 

47. Wiring for arresters is shown in figure 9. The arrester re- 
quired is the metal block, open-space cut-out used by most telephone 
companies. Tavo pairs of blocks are employed, one pair for each side 
of the line. One block of each pair is connected to ground, and the 
other to the line. The blocks are separated by a thin sheet of mica 
0.01 of an inch thick. This mica has an opening in the center to allow 
the lightning discharge to pass from one block to the other and 



20 

thence to ground. The blocks are held in place by a simple spring 
assembly. An air gap of 0.01 of an inch will break down at about 
350 volts pressure. 

XV. CARE or REGISTER. 

48. Oiling^ care of clock. — The bearings of the sprocket-wheel axis 
and the small guide roller for the chain should be oiled occasionally 
with clock oil. The clock movement of the transmitter being once 
wound up requires rewinding only at long intervals, for the clock 
movement is capable of making many electrical contacts without 
rewinding. 

49. Use of oil in float pipe, — During the winter when the surface 
of the water in the float pipe is likely to be frozen, the register may 
be kept in operation by means of a layer of 5 or 6 inches of cylinder 
oil floating on the surface of the water. The oil should be poured 
into the float pipe so as to run down along the inside wall ; otherwise 
the oil falling on the float might cause injury. Of course, the float 
may be pulled up to the top of the pipe, but with a little care this 
should not be necessary. The oil also serves to stop the rusting of 
the iron piping, and tends to stop friction between the float and the 
float pipe, should the latter be slightly out of vertical, so that the 
float comes in contact with the pipe. 

50. Care of electrical contoxits. — Occasionally the mercury con- 
tact, B (see figure 2) , will need attention. The mercury will become 
fouled and require replacing, and the oxide should be scraped off the 
platinum pins that become corroded in time because of arcing of the 
electric current as the pins leave the mercury. Excessive arcing is 
an indication of too much battery voltage. 

51. Method employed in caring for register. — The care of the 
register should not involve any more trouble than that usually 
experienced with the other Weather Bureau instrumental equip- 
ment, and failures, if not obvious, may be corrected somewhat as 
follows : 

62. Suppose the indicator fails to keep step with the transmitter 
and the dials of the latter agree with an eye reading of the standard 
gauge. There are several possible sources of failure as follows, testa 
for which may be applied one after the other until the cause of the 
failure is located. 

53. (1) Strength of current.— Th^ strength of the electric current 
may be too low, so that either the rising or the falling magnets 
of the indicator fails to operate at times, and one may fail oftener 
than the other. 

54. Remedy. ~^QQ that the voltage of the battery is brought up to 
the value determined as correct when the register was first put in 



21 

operation (see paragraph 39) so that the action of the magnet is 
positive. 

55. (2) The mercury switch^ B, may occasionally fail to operate. 

56. Remedy. — Clean the platinum wires and renew the mercury. 

57. (3) Loose or corroded wires. — The connections of the wires to 
binding posts at either transmitter or indicator may be loose or 
partly corroded. 

58. Remedy. — Clean wires and fasten in binding posts carefully 
and tightly. If corrosion is occurring at the transmitter, a little 
vaseline rubbed on the posts and wire will help clean the holes in the 
binding posts. The rest of the brass parts of the instrument may 
be protected from corrosion likewise. 

59. (4) Wave action in the float pipe may cause rises and falls of 
the float that are not followed rapidly enough by the contact-making 
devices, so that more contacts may occur during a rise than during a 
fall or vice versa. This defect is fundamental and should not ordi- 
narily occur if the float pipe and nozzles have been properly designed 
and installed. 

60. Rewiedy. — Eeduce the size of the opening in the nozzle so that 
the wave action is effectively damped. 

61. (5) Failure of the indicating meclianism. — This should occur 
very infrequently, if at all. 

62. Remedy. — Operate the indicator with the transmitter detached 
and properly adjust the mechanism until there is positive action. 

63. Reporting trouble to central office. — If the above tests do not 
remedy the trouble, the matter should be reported to the central 
office and the defective apparatus replaced or such other action taken 
as is necessary. 

64. Use of telephone. — In making tests that require communica- 
tions between a man stationed at the transmitter and another at the 
office, a telephone should be used, if possible. If two local battery 
telephone sets are available the register wires themselves may be em- 
ployed for line wires. Otherwise the two persons making the tests 
must resort to some prearranged plan that is necessarily difficult to 
follow. 

65. Gleaning float pipe, — It will probably be necessary to clean the 
sediment out of the inlet pipes every few years or oftener, because 
the lower end of the float pipe with which no inlet pipes are used 
may become obstructed. This cleaning can be effectually done only 
when there is low water, and the removal of the nozzles is necessary 
if mechanical cleaning is resorted to. It should be possible, however, 
to avoid the removal of the nozzles and accomplish the cleaning by 
running water into the upper end of the float pipe for a considerable 
length of time, using enough of it to maintain a high head of water 



22 



in the float pipe. A strong flow of water would then take place 
from the float and the inlet pipes to the river and a large part of the 
sediment should go along with the water. Of course the float would 
have to be removed. The water from a 1^-inch hose connected to 
the city supply should usually be sufficient, but in case the city supply 
is not available a i)ortable pump could be used and the water taken 
from the river. Some officials have had a locomotive tender placed 
at their direction for this purpose. 

66. Frequent attention required.— In general, it can be said that 
an automatic gage of this character can not be expected to give reli- 
able readings unless it is given frequent attention. " The idea that 
an automatic gage lessens the work of river observations is erroneous ; 
the work is very much increased, but the results obtained more than 

POST aKOUH:PE.-D 
O N ^ AS E- 








ARRE.STE.RS 



XT 



TRANS MfTTE.-R, 

Fig. 10. — Wiring diagram for recorder or telei'egister. 

compensate the office for the increase in work." (Montrose W. Hayes, 
official in charge, St. Louis, Mo.) 

XVI. WATER-STAGE RECORDER. 

67. At a few river stations the indicator has been replaced by a 
recorder. Telethermograph recorders of the kind shown in figure 11 
are used for this purpose, suitable record sheets being provided to 
correspond to the range of river stages at the station. The diagram 
of circuits for this recorder and its connected transmitter is shown 
in figure 10. It is possible to operate the indicator along with the 
i-ecorder at the same time, but such an arrangement may usually be 
dispensed with. This is accomplished by the wiring indicated by 
dotted lines in the figure, a local battery being used between the 
recorder and indicator. 






TELEREGISTER FOR USE IN PLACE OF INDICATOR. 



INDEX. 



Paragraph. 

Arresters, lightning. 47 

Base plate, attachment of 7 

Battery, local - 67 

type of, used 35 

Brackets for attachment of fioat pipe to pier 8,20 

Cover, copper, for transmitter 11 

Cap, malleable iron 18 

Clock, care of 48 

Conduit, use of 38 

Contacts, electrical, care of 50 

Corrosion, protection of iron from 19,30 

Counterweight 2, 9 

Current, electric, strength of 40, 53 

voltage of 39 

Dials, transmitter, reading of 10 

Float, copper 9 

Grounds, method of making 37 

Indicator, arrow point of 12 

description of 12 

installation of 33 

location of 2 

readings of 2 

remedy for failure of 01,62 

setting of— 45 

Ladder, iron 28 

Lightning, protection against 46, 47 

Material, list of 19,31 

Nozzles, cast-iron 6, 17,24 

furnishing of 17 

size of opening in 6 

Oiling mechanism 48 

Oil, use of, in float pipe 49 

Pipe, counterweight 2, 7, 18,25 

assembly of 18,25 

height of 18,25 

float 2 

assembly of 15, 22 

attachment to bridge pier of 8 

cleaning 65 

cover plate 9 

height of, above pier 7 

location of 4 

possible injury to 8 

typical installation of 

use of oil in 49 

verticality of 1*>, 23 

inlet 2, 6 

23 



24 

raragraph. 

Pipes, spacing of float and counterweight 18 

Plate, iron cover, for float pipe 9 

Platform at top of float pipe 20,26 

Platform, handrailing for 27 

Proposals for work, securing of 14 

Recorder, water-stage, installation of l 33 

use of 67 

Record sheets 67 

Rf^gisters, water-stage, Friez 1,3 

Marvin, adjustment and operation of 39-45 

arrangement of parts 2 

care of 4»-66 

frequent attention required in care of 66 

installation of 13 

method used in care of 51 

site for 13 

types of 1 

Relays, use of 42 

Reporting trouble to central office 63 

Site for register 13 

Specifications and drawings, preparation of 13 

Specifications, sample, for piping on outside of pier 15-19 

for piping within pier 20-30 

Switch, mercury 9,55 

Tape, perforated bronze 2,9 

Telephone, use of 64 

Top flange, attachment of 7 

Transmitter, approach to 13 

description of 9 

exposure to weather of 11 

installation of 32 

location of 2 

Wave action, damping of 6,59 

Wire and battery service 18,34 

Wire, size of. for circuits 35,38 

Wires, loose or corroded, remedy for 58 

Wiring, methods of 36 

permanency of 38 

o 



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